Feeding device for rock drills



Nov. 1o, 1931.

C. C. HANSEN FEEDING DEVICE FOR ROCK DRILLS y Filed Feb. 19, 1929 INVENTOR Yjfam sen/ HIS A T/E i the threaded end S2 Patented Nov. 10, 1931 CHARLES COMPANY, OF JERSEY CITY, NEWJERSEY, A CORPORATION OF'NEW JERSEY FEEDING navos non. BooK nnILLs Application filed This invention relates to rock drills, but more particularly to a feeding device for rock drills.

The object of this invention is to enable the construction of a feeding device of the pressure fluid operated type whereby a piston in the cylinder placed rearwardly of the rock drill shell may be ope-rated Ion by pressure fluid at the end having the greater eX- posed area to cause pressure on that end to retract the drill from the work. By means of this device that side of the'piston adjacent the piston rod is acted upon by pressure fluid to cause the rock drill to be moved toward the rock surface being drilled. V

The object is attained by the mechanism shown in the accompanying drawings, in which rock drill shell and feeding cylinder partly in cross section, and

Figure 2 is a vertical cross sectional'view of the rock drill and shell taken on the line 2-2 of Figure 1 looking in the directionindicated by the arrows.

.Referring more particularly to the draw ings, a rock drill 4 is slidably mounted on the guides 6 of a rock drill shell or cradle 8. rl`he shell 8 is of substantially standard construction having the usual conical projection 1() for securing the shell to a quarry bar (not shown) or other supporting means. A cylinder 12 is secured to the rock drill shell 8 by means of bolts 14 and 16 or the cylinder 12 i' may be integral with the shell 8. A back head 18 forms a closure for the rearward end of the cylinder anda cylinder head 2() having an aperture 22 provides a closure for the forward end of the cylinder 12. i piston 24 slidably mounted in the cylinder 12 has a piston rod 26 attached thereto by means of a reduced portion 28 and a'nut 30 screwed onto of the reduced portion. Packing means 34 prevents leakage of pressure iuid from the forward end ofthe cylinder. The piston rod 26 passes through an aperture 36 in the packing means 34 and the protruding end 38 of the piston rod is serrated to form a rack 40.

y A rack 42 is formed onl the under side of y ion 44 which February 19, 1929. serial No. 341,106.

C. HANSEN, 0F EASTON,` PENNSYLVANIA, ASSIGNOR TO INGERSOLL-RANI) the rock drill 4 and a pinion 44 rotatably mounted on a shaft 46 which passes transversely through the'shell 8 is secured in place by pins 48. Spacers hold'the pinion 44 centrally in the shell 8.'

A; throttle valve casing 521s secured to the rearward end ofthe cylinder12 and latwway throttle valve 54 operatively connected.,

to a throttle valve handle 56 is mounted therein. `Pressure `fluid conduits 58 land() convey pressure fluid from `the throttle valve to the front and rear ends respectively of the cylinder 12 and a pressure'fluid supply pipe 'G2 carries pressure fluid vto the throttle valve chamber 'from a source of supply (not shown). l n Y The operation of the feeding device is as follows: Assuming the rockk drill vand shell Figure 1 is a longitudinal elevation of the drilled, the operator turns the throttlevva'lve intov the position shown in Figure 1. This k'permits pressure fluid to be exhausted from the front end ofthe cylinder 12 through the conduit 58 and out of an exhaust port 64 in the throttle valve casing A52. At the same time pressure fluid is admitted to the conduit 60 thence to the rearward end of the cylinder 12. The pressure fluidacts upon the rearward face of the vpiston 24 forcing it down- 'The motion of the piston 24 is transmitted through thel rack" 40 tothe pinis caused to revolvein a clockwise direction. The pinion 44 acts upon the rack 42 to lift the rock drill 4 away from the rock surface. When it is desired to advance the Vdrill toward the work, the throttle valve 541s turned so that pressure liuid passes from the conduit 62 into the conduit 58 forcing the piston rearwardly to the position shown in the drawings. At the same time pressure fluid is exhausted from the rearward end vof the cylinder 12 through the conduitA l60 'and out of the exhaust port 64. i Y i lt should be noted that'the motion imparted to the rock drill is always in the reverse direction to the motion of the piston 24. By means of this device it is possible to apply a greater force for lifting the rock drill than Aprising a rock drill, a ,rock drill i .v ating with the rack on `with the rack on the rock drill, a pressure specification.

would be possible if the reversing means described above was not used, for it will readily be seen that the effective area of the piston on the side away from the piston rod is considerably larger than the area on the side from which the piston rod extends. This also makes it possible to use a cylinder .of smaller diameter than would be necessary in a device in which the rock drill moved in the saanedirection asthe pist-on. It also permits of the placing of the feedingcyli-nder on the rearward end of the rock drill away from the surface of the rock thus the objects hereinbefore mentioned are attained.

v I claim:

l. A feeding device for rock drills comshell, a cylinder'mounted in the shell, a piston reciprocably mounted in the cylinder, a piston rod attached to said piston, a rack on the rock drill, a rack on the piston rod, means for selectively admitting pressure fluid to either end of the cylinder to cause the piston to move.

and .a pinion cooperating `with the racks to transmit movement of the pist-on to the rock drill inthe reverse direction.

2. A feeding device for rock drills comprising a rock drill, a rock drill shell, a cylinder mounted on the shell, a piston reciprocably mounted in the cylinder, a piston rod attached to the piston, a rack on the piston rod, a rackon the rock drill, a pinion rotatably mounted on the sl1ellsaid pinion cooperthe piston rod vand Huid distributing valve mounted on the cylinder to selectively admit pressure iiuid into either end of the cylinder to cause the piston to move in one direction or the other whereby therock drill is caused to move in the direction opposite tothe movement of the piston through the medium of the racks and the pinion. c

3. A feeding device for rock drills, comprising a rock drill and a shell, a feeding cylinder extending rearwardly from the shell, a piston in thecylinder, a pistonfrodsecured to the piston and projecting forwardlyfrom 'i the cylinder towards the rock drill, means for selectively admitting either end of the cylinder piston and the piston rod, and rack and pinion means associated with the piston rod and the rock drill adapted upon movement of the piston rod in one .direction to cause movement of the rock drill in the opposite direction.

Init'estimony whereof I have signed this CHARLES c. HANSEN.

pressure fluid to to reciprocate the being operated upon `and c 

